BALTIMORE — When the Boston Red Sox finished with the Orioles on Sunday, it didn’t take any complicated analytics to illustrate how large the gap is between first place and last in the American League East.

The Red Sox completed a four-game sweep of the O’s with a 4-1 victory before an announced Camden Yards crowd of 25,303, showing again why they are so easily the winningest team in the major leagues.

Left-hander Chris Sale, who appears to be the best pitcher in the sport at the moment, showed why. He struck out 12 Orioles in five innings and was on pace to set the major league record for strikeouts in a single game (20) when he was pulled off the mound to protect his golden arm.

He was about as unhittable as you can get without pitching a no-hitter, giving up just one single and walking none on the way to his 12th victory. With the 12 strikeouts, he re-assumed the major league lead in that category with 219, pending Washington Nationals ace Max Scherzer’s Sunday night start against the Chicago Cubs. The five scoreless innings dropped Sale’s ERA to 1.97, which leads the American League.

“Sale took it to a different level,” Orioles Manager Buck Showalter said. “He was carrying a lot of fastball. The first fastball he threw today was 98 [mph]. The second one was 99. He was throwing a changeup at 88 and 90. That didn’t seem fair.”

The only thing that kept Sale from continuing to dispatch the Orioles at a record strikeout rate was an abundance of caution on the part of Red Sox Manager Alex Cora. Sale was making his first start since going on the 10-day disabled list with a sore shoulder, so it made perfect sense to remove him after he threw just 68 pitches.

“He’s been on the DL a little bit and he came off fresh,” Orioles shortstop Tim Beckham said. “He was sharp, man. He was sharp. He was back-dooring the curveball on the black whenever he wanted and he was reaching back and getting 99 whenever he wanted. Whenever you face Sale you just want to grind out at-bats and put together quality at-bats, and good things will come from that. We weren’t able to put it together today off of him.”

The only Oriole to hit safely against him was Renato Núñez, who lined a single to left field in the fourth inning.

Sale has been so dominant in his past seven starts that his 0.20 ERA over that span is — according to @MLBStatoftheDay — the lowest by a Red Sox pitcher for seven straight starts since the statistic became official in 1913.

Meanwhile, Orioles starter Alex Cobb (3-15) continues to pitch well and, with an exception or two, keeps getting beat anyway. He pitched seven strong innings, allowing just two runs (one earned) on six hits and striking out seven. The effort might have paled next to Sale’s, but it was the third time in a row that Cobb pitched at least six innings and allowed just one earned run.

“The results are good,” Cobb said. “I’m very happy with the way the line looks after those games, but there’s a lot of things where you look at the game within the game of pitching and mistakes that you might get away with here and there that you know aren’t sustainable throughout the course of a season or just a long stretch.

“I’m missing a lot with certain things that I probably won’t say in the media. There’s things that I can get better at. That will be the fine-tuning part. Once I get that, I can’t tell you the results are going to get any better, but I’ll feel better about what I’m doing.”

His only real mistake was the pitch that former Oriole Steve Pearce hammered over the left-field fence in the first inning. The other Red Sox run off Cobb came in the fourth inning when Brock Holt scored all the way from first base on a softly hit flyball double by J.D. Martinez that Adam Jones bobbled for an error.